This invention relates to a noise barrier wall and, in particular, to a serpentine noise barrier wall.
A serpentine noise barrier wall is described in U.S. Pat. No. 4,558,850. This type of barrier wall is typically erected along roadways to isolate surrounding properties from vehicular noise and to prevent pedestrians and animals from straying onto the roadway. Typically, the serpentine wall is made up of pre-cast, concrete panels that are joined together at vertically-disposed, abutting joints to form a zig-zag like structure. The angular displacement between adjacent panels is dictated by expected wind loading, the height of the wall and, to some extent, by the topography of the terrain.
Serpentine barrier walls utilizing hinged joints are also described in U.S. Pat. Nos. 3,732,652 and 4,111,401. Here, the panels generally contain a rounded surface along one side edge and a circular groove along the opposing side edge. In assembly, the rounded surface of one panel is inserted into the circular groove of a second panel and the panels set at a desired angle within the degree of freedom afforded by the joint. The panels, once set in place, are locked at the desired angle using various types of devices such as cables and swivel pin assemblies. Although this type of hinged joint provides for a great deal of flexibility, the male and female sections making up the hinged joints are difficult to cast and can be easily fractured or broken during transportation, handling and erection of the panels.
The joints between the adjacent panels of some serpentine walls are oftentimes relatively weak and footings must be placed beneath each joint to help support the panels in assembly. Relatively long walls, therefore, require a large number of footings. These footings require a good deal of time and effort to prepare and thus increase the manufacturing erection costs.